Ooof! I'm sorry, Ozzie. Exhausting and lonely hits the nail on the head. But that doesn't mean you're "falling short," by any means! The fact that you can see you are doing better than a year ago is TREMENDOUS!
I think overwhelm/exhaustion/loneliness are reasonable responses for folks in our situation. I mean, it is a LOT of work to take good emotional, physical, financial, and spiritual care of myself; and that would be true if I wasn't living with someone whose ST is only broken by logistical negotiations, verbal attacks and rage.
It's only recently (last several months) that T (x3) ALL raised BPD and I started learning more about it. Before that, I was trying to make sense of my experience based on H's other diagnoses (BiPD and addiction). While there are some very important overlaps -- as other places on this site discuss -- what I'm seeing and learning now has helped me realize why I still didn't feel I was making any progress in my own attitude and approach to living. Recognizing the BPD part helps me
accept acknowledge how very hard I've been working and why all the work I'm doing on myself hasn't lightened the dysregulation at all (I'm still not always in acceptance about it).
I can watch another driver spin out on ice, but I can't stop their car. I can only take actions to steer my own vehicle out of the way, and try to help D do the same.
Sometimes I get stuck, pulled over on the side and staring at the patch of ice and the approaching vehicle trying to predict or avoid disaster. Other times, I'm stuck, but at least I'm sitting in a warm car with a latte.
I'm so glad you're here, because you and the other members of this site have already really lightened the burden for me.